Paper roll filter structure



April 1970 G. E. BRAYMAN 3,504,803

PAPER ROLL FILTER STRUCTURE Filed June 8, 1967 INVENTOR.

George E Bmyman By Dav/s, Hox/e, Faith/all 8 Hapgood Af/omeys United States Patent "ice 3,504,803 PAPER ROLL FILTER STRUCTURE George E. Brayman, Brewster, N.Y., assignor, by mesne assignments, to Eagle Empire Corporation, White Plains, N.Y., a corporation of New York Filed June 8, 1967, Ser. No. 644,572 Int. Cl. B01d 27/04 U.S. Cl. 210439 3 Claims ABSTRACT OF THE DISCLOSURE A filter unit using a paper (or like material) roll having a central opening as the filter element, said roll having its ends positioned between contiguous perforated end plates, in which the liquid to be filtered passes through the filter in a direction parallel to the longitudinal axis of the central opening of the paper roll and wherein the base plate at the liquid exiting end of the roll has inner and outer annular wedge members disposed such that they penetrate the paper roll (when in place) near the inner and outer edges of the end of the roll, The annular wedges effect radial stresses that compress the outer layers of the roll against the inner wall of a surrounding container and the inner layers against the outer wall of a core element disposed in the central opening.

Filters are commonly used in recirculating liquid systems such as, for example, lubrication systems of reciprocating engines. Such filters remove particles of dirt, metal, or other foreign matter as well as water from the lubricating oil. However, conventional filter elements fail to trap and retain particles of very small size and consequently, it is necessary to change the lubricating oil frequently.

It has been recognized that a roll of absorbent paper, such as toilet tissue, provides a large surface area with a porosity that will remove particles of a size not removed by conventional filter medium used in reciprocating engine systems, for example, filter elements used in automobiles.

In the past, filter units have been designed which utilize a paper roll as the filtering medium. See U.S. Patent No. 2,750,048.

This invention is an improvement on said prior paper roll filters in its manner of effecting the seal between the roll and contiguous surfaces of containing members lying parallel to the layers of the paper roll. A further feature of this invention is the provision of wedge means for directing stresses inwardly from both inner and outer portions of the liquid-exiting end of the roll, thereby compressing the layers of paper.

The drawing is a cross sectional view of an oil filter unit according to the present invention.

In the drawing, a cup shaped metal canister 1 is removably affixed to an end closure or headpiece 9 by screw threads 26, a bayonet lock, or other locking means. A paper roll filter element 20 is positioned within the canister 1 about a central core tube 3. The roll 20 may be wound about a cardboard tube 27. The central core tube 3 is affixed to a perforated end plate 5 which extends across one end surface of the paper roll 20. The opposite end of the core tube 3 is provided with a finger bail 4 to permit ready removal of the spent filter element.

A base end plate 6 is positioned between the filter paper roll 20 and the headpiece 9. Base plate 6 is provided with an annular wedging surfaces 12 through 15. The wedge surfaces are forced into the end of the paper roll 20 when the headpiece 9 is seated in position in the canister 1. Wedge surface 15 forces the innermost plies of paper roll 20 into sealing engagement with the ex- 3,504,803 Patented Apr. 7, 1970 terior of the core tube 3. Wedge surface 12 forces the outermost plies of paper roll 20 into sealing engagement with the interior of the canister 1. Wedging surfaces 13 and 14 cause radial compression of the intermediate plies of the paper roll 20.

A plurality of oil flow apertures 16 and 17 are provided in the base plate 6 and the end plate 5 respectively. Headpiece 9 is provided with a quick disconnect outlet fitting 10 which leads from outlet chamber 23 in communication with base plate apertures 16. At the opposite end of the paper roll filter element 20, end plate apertures 17 are in communication with an inlet chamber 2. Inlet chamber 2 leads from the interior of core tube 3 which is in communication with a quick disconnect inlet fitting 11. O-rings 7 and -8 are provided to effect appropriate seals among the various elements, Screens 21 and 22 prevent pieces of paper from the roll or other large particles from entering the lubrication system.

In operation, oil or other liquid, to be filtered enters the filter unit under pressure from the engine through the inlet fitting 11. The oil enters the interior of core tube 3 and travels to the inlet chamber 2 where it is distributed about the upper or inlet end of paper roll filter element 20. The oil passes through apertures 17 in end plate 5 and flows downwardly between the plies of paper toward the lower or outlet end of the filter roll 20. Particles of foreign matter are trapped between the paper plies and water which may be present is absorbed by the paper. The clean, filtered oil emerges from the lower end of the filter roll and passes through apertures 16 in the base end plate 6 to outlet chamber 23. The clean oil then exits from outlet chamber 23 through outlet fitting 10 to suitable piping for return to the engine.

No oil can escape passing through the filter roll 20 since wedge surfaces 12 and 15 seal the innermost and outermost plies of the roll to the inner surface of canister 1 and the outer surface of core tube 3, respectively. Channels cannot develop between plies of the roll since wedge surfaces 13 and 14 exert a radial compressive force on the remainder of the roll at the inlet end. Such force precludes buckling of the plies and thus arrests channeling at its inception. In addition, the compression of plies of the roll reduces the space or clearance between the plies to thereby trap smaller particles than can be removed by non-compressed paper rolls. The direction of oil flow tends to force the roll against the wedge rings.

I have found that a filter built in accordance with this invention will remove particles as small as .01 micron. Replacement of the filter element in such a filter unit at regular intervals dictated by operational conditions will keep engine oil sufliciently clean and free of contaminants to enable the user to avoid further oil changes. An engine equipped with such a filter may never require a change of oil.

The paper roll filter element is periodically changed by releasing quick disconnect fittings 10 and 11 and removing the filter unit from the lubricating system. The engine need not be stopped since such fittings seal when disconnected. Headpiece 9 is removed from the canister 1 by unscrewing or the release of other locking means. The base plate 6 is lifted from the canister containing the spent filter roll. The spent roll is easily removable because removal of the headpiece or closure 9 removes the axial force from base end plate 6 thereby permitting withdrawal of wedging surfaces 12 through 15-. Removal of the wedges allows the roll to relax from its previously wedged and sealed condition. The spent roll is easily lifted from the canister 1 by pulling on the finger bail 4. The bail 4 lifts the core tube 3 and the associated end plate 5 which transfers the lifting force to the inlet end of the filter roll 20. The spent roll can then be slipped from the core tube and support plate assembly. The canister and other parts can then be wiped clean.

A clean paper roll is slipped over the core tube 3 until it bears against the end plate 5. This assembly is then placed in the canister 1 and base plate 6 placed over the outlet end of the paper roll with the Wedge surfaces 12 through 15 placed against the end of the roll. Headpiece 9 is then fitted to the canister and screwed or otherwise secured in place thereby forcing the wedge surfaces into the end of the paper roll between the plies. The clean roll is thus clamped against the core tube 3 and against the inner wall of the canister 1 to effect seals to prevent bypass oil flow. The serviced filter unit is returned to its operative location and the appropriate inlet and outlet piping is then connected to their respective fittings.

The clean roll has air occupying the space between the plies as well as the pores of the paper. When oil under pressure enters the unit, the roll is radially compressed. The wedge surfaces 12 through 15 keep the outlet end of the roll in proper position by virtue of their clamping action, and thus preclude the possibility of an oil path being established externally of the now compressed filter. As air is purged from the filter and displaced by oil, the filter roll becomes less compressed and the clearance between plies becomes established.

Although, I have described in detail one embodiment of my invention, it is apparent that the invention may take other structural forms, may be used for filtering fluids other than oil, may use paper rolls especially fabricated for the purpose, and may otherwise be varied within the scope and spirit of the invention.

It is claimed:

1. In a filter unit for use with paper roll filter elements including a container, a removable end closure for said container, a hollow core element for supporting said paper roll, an outlet chamber arranged for communication with a first end of said paper roll filter element and with an outlet passage, and an inlet chamber arranged for communication with the other end of the paper roll and with an inlet passage, the improvement which comprises providing an end plate for said first end of said paper roll, said end plate being provided with radially spaced apart annular rings located adjacent the inner and outer edges of the said first end of the paper roll, said annular rings being provided with sloping wedge surfaces which are of sufiicient height to penetrate the said first end of the paper roll to force the plies of the paper proximate the outer and inner peripheries of the roll into sealing engagement with the container and the core element respectively.

2. The improvement of claim 1, wherein the hollow interior of the core element is in communication with the inlet chamber.

3. The filter unit of claim 1 wherein the annular rings are each provided with a second sloping wedge surface for radially compressing the plies of the roll intermediate the annular rings.

References Cited UNITED STATES PATENTS 1,753,809 4/1930 Short 210-494 X 2,525,287 10/1950 Cuno 210-443 2,661,846 12/1953 Lash et al. 210-494 X 2,750,048 6/1956 Hilbish 210-494 X 2,928,547 3/1960 Lawrence 210-494 X 3,308,956 3/1967 Yee et al. 210-232 3,317,045 5/1967 Dummler 210-494 X 3,317,053 5/1967 Dummler 210-494 X 3,319,790 5/1967 Lindberg 210-232 FOREIGN PATENTS 554,104 1/1957 Belgium.

REUBEN FRIEDMAN, Primary Examiner W. S. BRADBURY, Assistant Examiner US. Cl. X.R. 210-494 

